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Double-Parameter Solutions of Projective Riccati Equations and Their Applications

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Communications in Theoretical Physics 2007年第1期47卷 1-9页

作者： WANG Ming-Liang LI Er-Qiang LI xiang-zheng Science College Henan University of Science and Technology Luoyang 471003 China Department of Mathematics Lanzhou University Lanzhou 730000 China

The purpose of the present paper is twofold. First, the projective Riccati equations （PREs for short） are resolved by means of a linearized theorem, which was known in the literature. Based on the signs and values of coeffcients of PREs, the solutions with two arbitrary parameters of PREs can be expressed by the hyperbolic functions, the trigonometric functions, and the rational functions respectively, at the same time the relation between the components of each solution to PREs is also implemented. Second, more new travelling wave solutions for some nonlinear PDEs, such as the Burgers equation, the mKdV equation, the NLS^＋ equation, new Hamilton amplitude equation, and so on, are obtained by using Sub-ODE method, in which PREs are taken as the Sub-ODEs. The key idea of this method is that the travelling wave solutions of nonlinear PDE can be expressed by a polynomial in two variables, which are the components of each solution to PREs, provided that the homogeneous balance between the higher order derivatives and nonlinear terms in the equation is considered.

关键词： projective Riccati equations linearized theorem homogeneous balance Sub-ODE method travelling wave solutions nonlinear PDE

Study on liquid-filled structure target with shaped charge vertical penetration

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Defence Technology（防务技术） 2019年第6期15卷 861-867页

作者： Min Guo Xu-dong Zu Xiao-jun Shen zheng-xiang Huang School of Mechanical Engineering Nanjing University of Science and TechnologyXiaolingwei 200Nanjing 210094China Unit 63961 Peoples Liberation Army6th Beiyuan RoadChaoyang Beijing100012China

Based on the characteristic expanded hole of a shaped charge jet(SCJ) for target penetration and the reflow characteristics of liquids,the liquid-filled structure of a target disturbs the stability of the SCJ acquired in two independent *** interference jet speed interval,the escape jet speed interval,and the surplus depth are calculated on the basis of the virtual origin *** experimental results,including the velocity of the escaped jet tip and the surplus depth of penetration,are consistent with the theoretical *** show that the theory can describe the interaction process of the target with a shaped charge jet.

关键词： Shaped charge Liquid-filled structure target Disturbed jet Escape jet

The dominant driving force for supercontinent breakup: Plume push or subduction retreat?

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Geoscience Frontiers 2018年第4期9卷 997-1007页

作者： Nan Zhang Zhuo Dang Chuan Huang zheng-xiang Li Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking University Earth Dynamics Research Group ARC Center of Excellence for Core to Crust Fluid Systems(CCFS)and The Institute for Geoscience Research(TIGeR)School of Earth and Planetary SciencesCurtin University

Understanding the dominant force responsible for supercontinent breakup is crucial for establishing Earth＇s geodynamic evolution that includes supercontinent cycles and plate tectonics. Conventionally,two forces have been considered： the push by mantle plumes from the sub-continental mantle which is called the active force for breakup, and the dragging force from oceanic subduction retreat which is called the passive force for breakup. However, the relative importance of these two forces is unclear. Here we model the supercontinent breakup coupled with global mantle convection in order to address this question. Our global model features a spherical harmonic degree-2 structure, which includes a major subduction girdle and two large upwelling（superplume） systems. Based on this global mantle structure,we examine the distribution of extensional stress applied to the supercontinent by both subsupercontinent mantle upwellings and subduction retreat at the supercontinent peripheral. Our results show that：（1） at the center half of the supercontinent, plume push stress is ～3 times larger than the stress induced by subduction retreat;（2） an average hot anomaly of no higher than 50 K beneath the supercontinent can produce a push force strong enough to cause the initialization of supercontinent breakup;（3） the extensional stress induced by subduction retreat concentrates on a ～600 km wide zone on the boundary of the supercontinent, but has far less impact to the interior of the supercontinent. We therefore conclude that although circum-supercontinent subduction retreat assists supercontinent breakup, sub-supercontinent mantle upwelling is the essential force.

关键词： Supercontinent breakup Plume push Subduction retreat

Cytosinium Isophthalate: Crystal Structure Redetermination and Room Temperature Phosphorescence

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Chinese Journal of Structural Chemistry 2020年第9期39卷 1707-1713,1557页

作者： zheng Wen-Xu LI Tao xiang zheng HUANG Chang-Cang College of Chemistry Fuzhou UniversityFuzhou 350108China

The title compound cytosinium isophthalate(C-H2IA)self-assembly of cytosine(C)and isophthalic acid(H2IA)in aqueous media has been synthesized and the crystal structure with a reasonable protonation state is ***-crystal X-ray diffraction analysis reveals that each asymmetric unit contains one protoned cytosine molecule and one deprotoned isophthalic *** proton transferred from carboxylic acid to the pyrimidine ring is disordered across an inversion center with occupancy of 0.5 and the proton located to one of the carboxylate group lies on an inversion center shared by two crystallographically equivalent oxygen *** addition,the cytosine molecules are connected by complementary hydrogen bonds to form a one-dimensional tape *** neighboring isophthalic acids are connected via hydrogen bonds between carboxyl groups to form a one-dimensional lattice like ***,the adjacent organic base tapes and organic acid tapes are stacked one with another throughπ-πstacking interactions to form a three-dimensional supramolecular ***,C-H2IA displays a green phosphorescence in solid state at room temperature with the lifetime of 0.7 s determined by time resolved studies,indicating that supramolecular C-H2IA is a potential pure organic phosphorescent luminogens.

关键词： cytosinium isophthalate crystal structure redetermination room temperature phosphorescence supramolecular framework

Visible-light-driven photocatalytic inactivation of bacteriophage f2 by Cu-TiO_2 nanofibers in the presence of humic acid

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Journal of Environmental Sciences 2019年第3期31卷 383-391页

作者： Rong Cheng Mi Kang Zhi-peng Shen Lei Shi xiang zheng School of Environment & Natural Resources Renmin University of China

Pathogenic viruses in drinking water are great threats to public health. Visible-lightdriven photocatalysis is a promising technology for virus inactivation. However, the existing photocatalytic antiviral research studies have mostly been carried out in single-component systems, neglecting the effect of natural organic matter, which exists widely in actual water bodies. In this paper, electrospun Cu-TiO2 nanofibers were prepared as photocatalysts, and their photocatalytic antiviral performance in the presence of humic acid(HA) was comprehensively studied for the first time. The properties of the reaction mixture were measured during the reaction. In addition, the safety, reliability and stability of photocatalytic disinfection in the mixed system were evaluated. The results showed that the virus removal efficiency decreased with the increase of the HA concentration. The type of reaction solution, such as PBS buffer solution or water, did not affect the removal efficiency noticeably. Under acidic conditions, the electrostatic forces between photocatalysts and viruses were strengthened, leading to higher virus removal efficiency. As the reaction time went on, the pH value in the solution increased first and then tended to be stable, the conductivity remained stable, and the dissolved oxygen increased first and then decreased. The safety test showed that the concentration of Cu ions released into the solution was lower than specified by the international standards. No photoreactivation was observed, and the addition of HA significantly reduced the reutilization efficiency of the photocatalysts.

关键词： Photocatalysis Visible light Bacteriophage f2 Humic acid

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水电站边坡智能爆破设计与管控系统研究

爆破 2024年第2期41卷 60-66,95页

作者：郑祥邱浩扬王德明陈俊涛赵逢泽陈明中国水利水电第七工程局四川610081 武汉大学水资源工程与调度全国重点实验室武汉430000

水利工程爆破施工具有周期长、规模大的特点,传统爆破设计与施工管控方式难以满足当前水利工程的建设和发展要求,研究建立平台化、网络化、智能化的爆破设计与管控系统具有重大的工程意义。基于BIM、WebGIS和已开发的爆破设计软件,利用A... 详细信息

水利工程爆破施工具有周期长、规模大的特点,传统爆破设计与施工管控方式难以满足当前水利工程的建设和发展要求,研究建立平台化、网络化、智能化的爆破设计与管控系统具有重大的工程意义。基于BIM、WebGIS和已开发的爆破设计软件,利用Angular框架和SpringBoot框架,采用前、后端分离式方法开发了智能爆破设计与管控系统,系统由智能爆破设计模块、三维可视化模块、数字化爆破管控模块以及智能安全评价及预测预警模块四个功能模块组成,实现了智能爆破设计与全流程爆破审核功能一体化,能够根据现场实际施工情况,采用模型参数化动态联合裁剪方法,选取开挖轮廓线上的控制点进行智能爆破设计,生成爆破设计方案,并将设计方案上传审查,有效地促进了爆破全流程的标准化、信息化、数字化管理,加强设计、施工、监理等单位的实时交互办公。该系统在叶巴滩水电站边坡爆破开挖工程的应用结果表明,系统能有效进行爆破设计,并提高管控效率,可为水电站边坡爆破设计开挖施工提供技术支持。

关键词：智能爆破设计爆破管控 WebGIS BIM

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碳基材料复合水凝胶在吸附中的研究进展

塑料科技 2024年第7期52卷 135-140页

作者：王向鹏高艺伦李宴汝刘青霖张浩腾郑云香陈春茂中国石油大学(北京)化学工程与环境学院北京102249 山东石油化工学院化学工程学院山东东营257061 山东省碳中和绿色能源技术工程研究中心山东东营257061

碳基材料比表面积大,孔隙发达,表面有大量的含氧官能团,具有优异的力学性能。将碳基材料引入水凝胶体系中可以增加吸附位点,改善力学性能,丰富网络结构,实现优势互补,是研发高性能水凝胶吸附剂的主要思路。文章总结不同类型的碳基材料... 详细信息

碳基材料比表面积大,孔隙发达,表面有大量的含氧官能团,具有优异的力学性能。将碳基材料引入水凝胶体系中可以增加吸附位点,改善力学性能,丰富网络结构,实现优势互补,是研发高性能水凝胶吸附剂的主要思路。文章总结不同类型的碳基材料复合水凝胶的结构特点,重点介绍碳基材料对水凝胶的性能增强机制,综述复合水凝胶的制备方法及在水质净化领域的应用,分析碳基材料复合水凝胶吸附剂的前景、局限性和未来的研究潜力。

关键词：碳基材料复合水凝胶吸附改性机械强度

高脚竞速接力比赛中接力技术的研究——以第11届全国少数民族传统体育运动会为例

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当代体育科技 2024年第5期14卷 37-40页

作者：向慊向政朱欢陈芬孙先峰陈鑫湖北民族大学体育学院恩施市中等职业技术学校湖北恩施445000

该文以2019年全国第11届少数民族传统体育运动会高脚竞速4×100m接力比赛决赛的8支队伍为调查对象,通过视频分析、对比分析法、数理统计法等研究方法,对高脚竞速接力比赛中接力环节进行研究。研究表明:(1)决赛中8支队伍呈现出了行进间... 详细信息

该文以2019年全国第11届少数民族传统体育运动会高脚竞速4×100m接力比赛决赛的8支队伍为调查对象,通过视频分析、对比分析法、数理统计法等研究方法,对高脚竞速接力比赛中接力环节进行研究。研究表明:(1)决赛中8支队伍呈现出了行进间交接方式和静止式交接方式两种不同的交接技术;(2)决赛成绩由高到低排名为湖北队、贵州队、广东队、广西队、陕西队、四川队、湖南队、江西队;(3)行进间交接方式交接用时少,容易造成失误,而静止式交接稳定性高,但交接耗时相对较长。基于此,提出以下建议:(1)选择适用接力技术并合理训练;(2)加强特定环境训练,增强技术稳定性;(3)注重专项体能训练,奠定竞赛基础;(4)推进科技助力,科学化训练体系。

关键词：高脚竞速接力技术交接方式影响因素

Co-pyrolysis of sludge and kaolin/zeolite in a rotary kiln:Analysis of stabilizing heavy metals

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Frontiers of Environmental Science & Engineering 2022年第7期16卷 21-33页

作者： Qian Li Zhaoping Zhong Haoran Du xiang zheng Bo Zhang Baosheng Jin Southeast University Key Laboratory of Energy Thermal Conversion and Control(Ministry of Education)Nanjing210096China

Pyrolysis is a promising technique used for treating of sewage ***,the application of pyrolysis products is limited due to the presence of heavy *** this study,sewage sludge mixed with kaolin/zeolite was pyrolyzed in a rotary kiln,aiming to improve the immobilization of heavy metals in pyrolytic *** total concentrations,speciation distributions,leaching toxicities,and potential ecological risk indices of heavy metals in pyrolysis biochar were explored to examine the effects of kaolin/zeolite and pyrolytic temperature on immobilizing heavy ***,mineral composition and surface morphology of biochar were characterized by X-ray diffraction and scanning electron microscopy to reveal the potential mechanism of immobilizing heavy *** pyrolysis temperature facilitated the stabilization of heavy metals in pyrolysis *** proportions of stable heavy metals in biochar obtained at 650℃ were 54.50%(Cu),29.73%(Zn),79.29%(Cd),68.17%(Pb)and 86.70%(Cr).Compared to sewage sludge,the potential contamination risk index of pyrolysis biochar obtained at 650℃ was reduced to 17.01,indicating a low ecological *** addition of 7%kaolin/zeolite further reduced the risk index of co-pyrolysis biochar prepared at 650℃ to 10.86/*** characterization of biochar revealed that increase in the pyrolysis temperature and incorporation of additives are conducive to the formation of stable heavy *** study demonstrates that the formation of stable mineral compounds containing heavy metals is the key to stabilizing heavy metals in pyrolysis biochar.

关键词： Co-pyrolysis Sewage sludge Heavy metals Rotary kiln Immobilization mechanism